AMEC and Dakota Technologies Work on Groundwater Contaminant Detection

Aug 26, 2010

AMEC, the international engineering and project management company, has signed an agreement with Dakota Technologies to co-develop a subsurface contaminant-detection technology that could save billions of dollars in groundwater cleanup costs, according to a company press release.

Dense chlorinated solvents such as trichloroethylene (TCE) and perchloroethylene (PCE) are among the most common contaminants found in groundwater. However, the source zones of these denser-than-water contaminants cannot be precisely defined using current technology.

AMEC and Dakota are pioneering a technology capable of rapid, high-resolution, real-time mapping of such contaminant zones. It is a new laser-induced fluorescence (LIF) tool, referred to as DYE-LIF™ (patent pending), that is able to detect any type of non-aqueous phase liquid (NAPL) in the subsurface, regardless of its composition and innate ability to fluoresce. A hydrophobic, partitioning fluorescent dye is injected through a port in the LIF probe a few inches ahead of the LIF detector. If NAPL is present, the dye will dissolve into it and will begin to fluoresce. The fluorescence is then measured using Dakota’s standard optical detection equipment.

LIF technologies developed and commercialized by Dakota in the last 20 years have been invaluable for quickly delineating certain categories of NAPLs that naturally fluoresce. Unfortunately, many types of NAPLs such as dense chlorinated solvent NAPLs (DNAPLs), natural gas condensates, monoaromatic petroleum hydrocarbons, and aviation gas do not naturally fluoresce. The new DYE-LIF technology solves this problem and facilitates detection of all NAPLs, regardless of their composition.

DNAPLs such as the chlorinated solvents PCE and TCE are particularly troublesome because they can seep to depths hundreds of feet below the ground surface. The inability to accurately delineate DNAPL source zones is a major impediment to aquifer cleanup programs around the world.

“The DYE-LIF technology, if successful, will be a game-changer in our industry’s ability to characterize and remediate contaminant source zones,” says AMEC co-inventor Murray Einarson. “This technology should be especially effective for quickly defining DNAPL source zones, which hasn’t been possible using existing technologies.” Einarson noted that AMEC, Dakota, and researchers at the University of Guelph (Canada) recently submitted a proposal to the Department of Defense’s Environmental Security Technology Certification Program to demonstrate the new DYE-LIF technology at military sites in the United States.

According to Einarson, Dakota is starting a program to beta test the DYE-LIF technology at field sites with known or suspected NAPL contamination.